SO THE SEA. 



which is a movable float. As the bottle descends the stop-cocks must remain open, but as it 

 is hauled up again the flat float receives^the opposing 1 pressure of the vvatev above it, and, 

 acting by means of the connecting-rod, shuts both cocks simultaneously, thus inclosing a 

 specimen of the water at that particular depth. Self-registering thermometers were employed, 

 sometimes attached at intervals of 100 fathoms to the sounding-line, so as to test the 

 temperatures at various depths. For dredging, bags or nets from three to five feet in depth, 

 and nine to fifteen inches in width, attached to iron frames, were employed, whilst at the 

 bottom of the bags a number of "swabs," similar to those used in cleaning decks, were 

 attached, so as to sweep along the bottom, and bring up small specimens of animal 

 life coral, sponges, &c. These swabs were, however, always termed " hempen tangles " so 

 much does science dignify every object it touches ! The dredges were afterwards set aside 

 for the ordinary beam-trawls used in shallow water around our own coasts. Their open 

 meshes allowed the mud and sand to filter through easily, and their adoption was a source 

 of satisfaction to some of the officers who looked with horror on the state of their usually 

 immaculate decks, when the dredges were emptied of their contents. 



Not so very long ago, our knowledge of anything beneath the ocean's surface was 

 extremely indefinite ; for even of the coasts and shallows we knew little, marine zoology and 

 botany being the last, and not the earliest, branches of natural history investigated by men 

 of science. It was asserted that the specific gravity of water at great depths would cause the 

 heaviest weights to remain suspended in mid-sea, and that animal existence was impossible 

 at the bottom. When, some sixteen years ago, a few star-fish were brought up by a line 

 from a depth of 1,200 fathoms, it was seriously considered that they had attached themselves 

 at some midway point, and not at the bottom. In 18G8-9-70, the Royal Society borrowed 

 from the Admiralty two of Her Majesty's vessels, the Lightning and Porcupine ; and in one 

 of the latter's trips, considerably to the south and west of Ireland, she sounded to a depth 

 of 2,400 fathoms,* and was very successful in many dredging operations. As a result, 

 it was then suggested that a vessel should be specially fitted out for a more important 

 ocean voyage round the world, to occupy three or more years, and the cruise of the Challenger 

 was then determined upon. 



The story of that cruise is utterly unsensational ; it is one simply of calm and unremitting 

 scientific work, almost unaccompanied by peril. To some the treasures acquired will seern 

 valueless. Among the earliest gains, obtained near Cape St. Vincent, with a common trawl, 

 was a beautiful specimen of the Euplectella, " glass-rope sponge/' or " Venus's flower-basket/' 

 alive. This object of beauty and interest, sometimes seen in working naturalists' and 

 conchologists' windows in London, had always previously been obtained from the seas 



* Most of the recorded examples of earlier deep-sea soundings have little scientific value. Unless the sounding- 

 line sinks perpendicularly, and the vessel remains stationary to do which she may have to steam against wind and 

 tide or current it must be evident that the data obtained are not reliable. From a sailing vessel it is impossible to 

 obtain absolutely reliable soundings except in, say, a tideless lake, unruffled by wind. It is very evident that if the 

 sounding lino drags after or in any direction from the vessel, the depth indicated may be greatly in excess of the truo 

 depth ; indeed, it may be double or treble in some cases. There is one recorded example of a dcptl if 7,706 fathoms 

 having been obtained, which too evidently comes under this category. After several years' soundings on the part of 

 the Challenger and the United States vessel Tuscarora, it has become probable that no part of the ocean lias a clopth 

 much greater than 4,500 fathoms. But even this is upwards of five miles! 



